06 Plant Water Relation - part 01 - Properties of water

06 Plant Water Relation - part 01 - Properties of water



Water :
  • Plant obtains variety of substances like water, minerals, nutrients, food and gases like O2 and CO2, from its surroundings. 
  • Productivity in plants is mainly affected by the non-availibility of water. Water is considered as `elixir of life'. 
  • Water constitutes almost 90 to 95% of most plant cells and tissues. 
  • Water helps the cells to maintain turgidity and shape. 
  • It shows following properties due to which it has great biological importance.

Properties of water: 
  • It is in the liquid form at room temperatureand is the best solvent for most of the solutes. 
  • It is inert inorganic compound with neutral pH when in pure form. 
  • Due to this, water is best transporting medium for dissolved minerals and food molecules.
  •  It is best aqueous medium for all biochemical reactions occurring in the cells. 
  • It is an essential raw material for photosynthesis. 
  • Water has high specific heat, high heat of vaporization and high heat of fusion. Due to this, it acts as thermal buffer. 
  • These various properties are due to hydrogen bonds between the water molecules.
  • Water molecules have good adhesive and cohesive forces of attraction. 
  • Due to high surface tension and high adhesive and cohesive force, it can easily rise in the capillaries. 
  • It is therefore, a significant molecule that connects physical world with biological processes.

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